DESCRIPTION: (adapted from the applicants abstract) The applicant and his co-investigator, Dr. Gerry Cunha, have focused their studies on the cellular and molecular mechanisms of estrogen action on developing and adult prostate with an emphasis on the role of tissue age on cell-cell interactions, estrogen receptors, growth factor pathways. The hypothesis suggested states that estrogens and androgens and the developmental control of prostatic cell growth may be regulated by cell-cell interactions mediated by the local production and action of peptide growth factors. In the first aim, Dr. Dahiya proposes to look at the estrogenic effects on prostate of the neonate and adult mouse using both wild-type and estrogen receptor knock-out mice. Next he will categorize growth factor and receptors during estrogen induced prostatic squamous metaplasia. The role of mesenchymal-epithelial interactions in the estrogenic response of the prostate will be examined. Finally, the applicant will analyze cellular and molecular pathways of estrogen action in neonatal prostates.